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Mar. 28, 2014

In the business of investigating antimatter

Stefan Ulmer, Initiative Research Scientist

picture of Stefan Ulmer

Ulmer Initiative Research Unit

Please describe your role at RIKEN.

My research unit is leading the Baryon Antibaryon Symmetry Experiment (BASE) at CERN (European Organization for Nuclear Research), which aims to measure the magnetic moments of the proton and antiproton with a fractional precision of one part per billion or greater. The experiment will be conducted at CERN’s antiproton decelerator in Switzerland and is strongly supported by RIKEN. My unit is also involved in the antihydrogen research driven by Yasunori Yamazaki’s Atomic Physics Laboratory at RIKEN.

How did you become interested in your current field of research?

High-resolution observations of antimatter offer very sensitive tests for CPT (charge, parity and time reversal) invariance, which is the most fundamental symmetry in the standard model of particle physics. Achieving such high-precision observations requires the construction of very accurate apparatus and the development of novel, pioneering techniques. I am fascinated by both the pioneering technical work required to develop ultraprecise machines as well as the strong impact of our tests upon the field of physics. The research is very important and exciting.

What made you decide to become a scientist?

I chose physics because it is both challenging and useful. In principle, with a good physics background you can work in all of the technical, engineering and mathematical fields. Physics offers insight into the symmetries of nature and engages in interesting philosophical questions.

How and when did you join RIKEN?

I was keen on getting into the antimatter business because antihydrogen physics is an exciting area of research and I had already developed techniques to measure the magnetic moment of the proton, which can also be applied to the antiproton. I was impressed by Yamazaki’s personality and knowledge and became convinced that working with him would be good for me. In 2011, I joined his lab at RIKEN as a foreign postdoctoral researcher, and in April 2012 I received an Initiative Research Unit (IRU) grant.

What is the best thing about working at RIKEN?

Image of Stefan Ulmer at CERN © 2013 RIKEN

The support available to researchers from all levels of staff at RIKEN—including IRU assistants, the Global Relations and Research Coordination Office, other principle investigators and the directors of centers—is impressive. Whenever I face difficulties there is immediate and strong support from many individuals.

Please tell us about your professional and personal goals.

My professional goal is to measure the magnetic moments of the proton and the antiproton with ultrahigh precision, and to develop a machine to refine the sensitivity down to parts per trillion and beyond. I also aim to apply sympathetic laser cooling of antiprotons to accelerate experiment cycles and improve antihydrogen production for high-precision measurement of ground-state hyperfine splitting of the antiatom. My personal goal is to enjoy life with my wonderful family.

How do you balance family life with your work at RIKEN?

Work–life balance is not an issue if work is fun. My family, specifically my wife Eva, is very supportive and generous.